Airship.



i. ANDERSSON.

-AIRSHI1,

APPUCATION FILED MAR. 1, 19!?- 1,250,124, Patented Dec, 18, 1917.

3 SHEETS-SHEET I.

I R f fl ANDERSSON.

AIRSHIP.

APPLICATION FILED MAR-7,1917.

Patented Dec. 18, 1917.

3 SHEETS-SHEET 2- l. ANDERSSON.

MRSHIP.

APPucATma mu) MAR. 1. 1917.

1,250,124. Patented Dec. 18,1917.

8 SHEETS-SHEET 3.

In z/erelo]:

I. ANDERSSON.

MRSHIP.

APPLICATION, FILED MAR. 1. 1917.

1,250, 124:. I Patented Dec. 18, 1917.

3 SHEETS-SHEET 3.

IVAN ANDEB-SSON, OF HEMPSTEAD, NEW YORK.

. AIRSEIP.

Specification of Letters Patent.

Application filed March 7,1917. Serial No. 152,990.

To all whom it may concern:

Be it known that I, IVAN ANDERSSON, a subject of the Kin of Sweden, residing at Hempstead, in t 'e county of Nassau and State of New York, have invented new and useful Improvements in Airships, of which the following is a specification.

The present invention relates to a dirigible aerostat of the non-rigid type with internal suspension, and consists of a combination of flexible tension members arranged in the interior of the balloon in order totransmit the load to the envelop and to. insure a symmetrical and uniform appearance of the balloon in cross-section.

If we had an atmosphere of hydrogen there would be a difference of pressure at difierent altitudes, just as we find a difference in pressure at different altitudes in our atmosphere of air. But as the specifi gravity of hydro en is only a fraction of that of air, the rop in pressure per unit height in an atmosphere 0 hydrogen would be a fraction only of the drop in-pressure 1 e Q, which is equal to the lift of the hydrogen per unit height in our atmosp re of air.

The equivalent conditions of a hydrogen atmosphere we find in the interior of a balloon inflated with hydrogen. 1 As the pressure drops at a slower rate inahydrogen atmosphere than in an atmosphere of air, the difierence in pressure of the two atmospheres will increase as we ascend above a fixed point. Therefore the relative pressure in the interior of a balloon is greater at the top than lower down.

In the present invention this condition is taken into consideration and a number of tension members are so arranged that any tendency of the said pressure to deform the envelop is obviated.

The invention is illustrated in the accompanying drawings, 7

Figure 1 showmg pressure curves for hydrogen and air, I

Fig. 2 a cross-section of a balloon showing forces acting on the envelop as a result of the atmospheric pressure of the hydrogen,

Fig. 3 a cross-section of a balloon showing forces acting on the envelop as a result of the inflated pressure in the balloon,

Fig. 4: a cross section of a balloon show- 4 ing all the resultant forces combined,

Fig. 5 a cross-section of a balloon showing an arrangement of the flexible tension memhere as it will be carried out in practice,

Patented Diec. 11.8, rear.

Fig. casts a dirigible balloon in elevav tion with a preferred suspension.

' Considering two atmospheres of' hydro-- gen and air respectively, having the same pressure at the lowest point-of the balloon,

their pressures will decrease above this point as illustrated in Fig. 1, by two curves, A for hydrogen and B for air. The horizontal lines between these two curves A and B indicate the relative pressure between the two atmospheres, 11. e. between the interior and the exterior of the balloon.

In Fig. 2 the relative pressures per unit area of envelop are indicated by arrows p, p, which represent forces acting'perpendicular to the"surface of the envelop E,"said forces belng resolved into their vertical components g, p and horizontal components 72 p P P P are the resultant vertical and horizontal forces acting at the four equidistant points 1, 2, 3, 4, on theenvelop E, and which composed give the resultants. R R B R acting on and in the directionof the tension members C, D, F, G. Theload librium.

4 g In a dirigible balloon of the non-rigid type it is necessary to add a certain amount of pressure to the gas which is generally accomplished by inflating balloonets with air. under pressure. This is done to prevent deformation of the envelop due to bending moments, nose pressure, and to counteract the pull of the suspension in an axial direction. This inflated pressure is equally distributed in all directions in the balloon as indicated by the arrows p 1%,, Fig. 3. The resultant forces R R R at the four equidistant points 1, 2, 3, 4, on the envelop E,-Fig. 3 are equal in magnitude and acting on and in-the direction. of the four tension members I, J, K, L, which are all joined at 0. By combining the two sets of tension members as described, and shown in Fig. 4: all lateral forces on the envelop due to the gas pressure and the load will be in equilibrium and a symmetrical and uniform cross-section of the balloon insured.

This combination of tension members as described is fundamental, but it is obvious that the resultant forces can be resolved into components and the direction of the tension members affected so changed as to bring the forces involved into equilibrium. It may even be necessary to remove or add some tension members. This has been done in an arrangement illustrated in Fig. 5. Here the two tension members F, G, have been removed and a horizontal member M substituted. The resultants R R have been resolved into their components P P acting on and along member M and being in equilibrium, and the two components P P acting on and along the members I, J, K, L, but not in equilibrium. To counteract these two forces it has been necessary to change the direction of the two members C, D, as indicated by C D to establish the desired equilibrium.

In carrying this invention into practice the members I, J, K, L, M, will preferably be made of rope netting or of permeable linen or cotton fabric, and the members C D will preferably be made of rope or cable in the usual way as illustratedby Fig. 6.

I claim:

1. In a dirigible aerostat, the' combination of a number of flexible tension members arranged in the interior of the aerostat and attached to the envelop so as to form four equidistant stretches, and bein so dis posed, that in conjunction with t e load they will establish an equilibrium of the forces acting at the points of attachment and as a result of the atmospheric pressure of the lifting gas, thereby insuring a uniform and symmetrical cross-section of the envelop.

2. In a dirigible aerostat, the combination of a number of flexible tension members arranged in the interior of the aerostat and attached to the envelop so as to form four equidistant stretches, and being so disposed, that they will establish an equilibrium of the forces acting at the points of attachment on the envelop, and as a result of the inflated pressure in the interior of the aerostat.

3. In a dirigible aerostat, the combination of two sets of flexible tension members arranged in the interior of the aerostat and attached to the envelop so as to form four equidistant stretches, and being so disposed, that combined, and in conjunction with the load, they will establish an equilibrium of the forces acting at the points of attachment on the envelop and as a result of the atmospheric and the inflated pressures of the lift ing gas, thereby insuring a uniform and symmetrical cross-section of the envelop.

In testimony whereof l have signed my name to this specification in the presence of two subscribing witnesses.

IVAN ANDElFtSEaQN.

W itnesses:

CHAS. E. PATTERSON, JOHN E. Lane. 

